INTAKE MEASURES AND SELECTIVITY OF PLANT PARTS CONSUMED BY FREE-RANGING ALOUATTA PIGRA IN A FRAGMENTED ENVIROMENT IN SOUTHEASTERN MEXICO.

Commonly in primate feeding ecology studies, the consumption of and preference for plant parts are based on time feeding. Through such studies, Howler monkeys (Alouatta spp.) are considered folivorous-frugivorous. However, there are few studies that estimate the real food mass consumed in the wild. We described the diet of black howler monkeys (Alouatta pigra) by three variables in two seasons in a fragmented environment in Balancán, Mexico. Focal behavioral observations were made from August-2012 to January-2013 (n=2600 min). We determined the time feeding (T=17% of total time), and the fresh weigh (FW=20842g) consumed of each plant part counting the food units (U=9541) carried to the mouth in each feeding bout. Every 15 days we weighed 100 food units of plant parts to estimate FW. Because each food needs specific handling we made a correlation test to establish if T invested relates with U and FW of each plant part. The items were consumed as follows (Items: %minutes/%FW): Mature leave: 34/21, Young leave: 24/11; Ripe Fruit: 20/35; Unripe Fruit: 5/30; Flowers: 11/3. We did not find a relationship between T and U (rs=0.26, R2=0.07, p<0.05) and FW (rs=0.1, R2=0.009, p<0.05). Our results indicate that Time feeding is an indicator of foraging effort made by howlers but not involve the food weigh consumed and probably does not reflect plant part preferences.